The present invention pertains to a speed limit monitoring system for vehicles, and more particularly to a speed limit monitoring system which reflects the speed tolerance profile of a driver.
Most roadways have a posted speed limit. However, posted speed limits are often ignored by a large number of drivers. These speeding drivers often drive recklessly at a speed well over the posted speed limit and are the cause of an appreciable number of road accidents. While the use of speed limit detecting systems is known in the prior art, most prior art speed limit detecting systems are not particularly practical or attractive to drivers and accordingly are not adopted or utilized.
U.S. Pat. No. 6,213,401 to Brown discloses a speed limit detecting system for detecting and displaying to a driver the speed limit on the roadway the driver is travelling on. The system includes bar coding indicia that is displayed on a road sign. The bar coding indicia graphically indicates predetermined information of the speed limit displayed on the road sign. A scanner is provided in the driver""s vehicle for scanning the bar coding indicia and for displaying the predetermined information to the driver. However, this system is costly and impractical due to the requirement of modifying civic signs to feature bar code symbols and to maintain the signs such that dirt and other debris does not obscure the bar code symbols.
Canadian Patent Application No. 2,186,790 to McKenna discloses a device for calculating and signalling excess vehicular speed to the vehicle occupants. Specifically, a transmitter is located within certain roadway objects and a digital signal of the lawful maximum roadway speed limit is transmitted to an in-vehicle signal receiving component which in turn sends the posted maximum speed digital value to the an on-board device that compares vehicle speed with the posted speed limit and which issues an alarm when the vehicle exceeds the limit. However, this system is costly and impractical due to the requirement of modifying civic signs to contain transmitters.
Accordingly, there is a need for a vehicle speed monitoring system which takes personal speed limit tolerances preferences into consideration, which is relatively easy to implement within a roadway network and which is attractive to vehicle owners for vehicle operation.
The present invention provides a system for monitoring the speed of a vehicle in relation to a posted speed limit, said system comprising:
(a) a GPS receiver for determining the location and speed of the vehicle;
(b) an input device on which a driver may select a speed tolerance profile; and
(c) a processor coupled to said GPS receiver and said input device for determining the posted speed limit, said processor including a comparator for comparing the speed of the vehicle with the posted speed limit and generating a warning when the speed of the vehicle falls outside the speed tolerance profile.
In another aspect, the present invention is a method for monitoring the speed of a vehicle, said method comprising the steps of:
(a) determining the location and speed of the vehicle;
(b) allowing the driver to select a speed tolerance profile;
(c) determining the posted speed limit that corresponds to the location of the vehicle;
(d) comparing the speed of the vehicle with the posted speed limit; and
(e) generating a warning when the speed of the vehicle falls outside the speed tolerance profile.
Further objects and advantages of the invention will appear from the following description, taken together with the accompanying drawings.